The chaos and confusion that follow emergencies and natural disasters have made it clear that communication and site management need improvement, and that the systems used today may not be reliable in an emergency.
In response to Homeland Security Presidential Directive 12 (HSPD 12), the US Federal government is issuing a single, trusted government-wide credential to all Federal employees and contractors. These IDs are designed to meet a common standard specified in the Federal Information Processing Standard 201 (FIPS 201). Each card has information about the individual's privileges and identity stored on it in a way that is secure and tamper-proof.
In the event of an emergency, those individuals classified as “first responders,” including doctors, police officers and firefighters could use their cards to gain access to the emergency site. However, it has been found that in present emergency response systems it is problematic to quickly check that the credentials and privileges stored on the cards are valid. This deficiency may be addressed by using the security cards for identification purposes only and have a secure credential database that transmits attribute information to a device used for controlling access to a secure area.
However, for privacy and security reasons, it may be desirable to protect from unauthorized viewing the transmission of the attribute information for individuals requesting access to a secure area. It is known that such transmission could be protected via a secure hardwired transmission line. However, a secure hardwired transmission line is not cost effective for many applications and, of course, is not an option in instances where wireless communication is used. Thus, in some cases it may be useful to encrypt attribute information. One mechanism for encryption of the attribute information uses asymmetric encryption, such as a public key encryption system. A public key encryption system uses two keys—a public key that may be known to anyone and a private or secret key that is not widely known. When a first user (user A) wants to send a secure message to a second user (user B), he uses user B's public key to encrypt the message. User B then uses her private key to decrypt it. The public and private keys are related in such a way that if the public key is used to encrypt messages, then only the corresponding private key can be used for decryption. For various examples, and further discussion, of public key encryptions systems, see U.S. Pat. Nos. 6,766,450, 6,487,658, and 6,301,659 all to Micali, which are incorporated herein by reference.
A drawback to public key encryption is that it can be costly to administer and maintain for a high volume of users. Thus, such a system may not be cost effective in some situations.
Accordingly, it is desirable to provide a cost-effective system that provides for the efficient protection of transmitted non-public attribute information.